Default constructor.

For fixed-size matrices, does nothing.

For dynamic-size matrices, creates an empty matrix of size 0. Does not allocate any array. Such a matrix is called a null matrix. This constructor is the unique way to create null matrices: resizing a matrix to 0 is not supported.

See also

resize(Index,Index)

Example:

Array<int, 1, 6> a(1, 2, 3, 4, 5, 6);
Array<int, 3, 1> b {1, 2, 3};
cout << a << "\n\n" << b << endl;

Output:

1 2 3 4 5 6

1
2
3

See also

Array(const std::initializer_list<std::initializer_list<Scalar>>&)

Array(const Scalar&), Array(const Scalar&,const Scalar&)

Constructs an array and initializes it from the coefficients given as initializer-lists grouped by row. [c++11]

In the general case, the constructor takes a list of rows, each row being represented as a list of coefficients:

Example:

ArrayXXi a {
  {1, 2, 3},
  {3, 4, 5}
};
cout << a << endl;

Output:

1 2 3
3 4 5

Each of the inner initializer lists must contain the exact same number of elements, otherwise an assertion is triggered.

In the case of a compile-time column 1D array, implicit transposition from a single row is allowed. Therefore Array<int,Dynamic,1>{{1,2,3,4,5}} is legal and the more verbose syntax Array<int,Dynamic,1>{{1},{2},{3},{4},{5}} can be avoided:

Example:

Array<int, Dynamic, 1> v {{1, 2, 3, 4, 5}};
cout << v << endl;

Output:

1
2
3
4
5

In the case of fixed-sized arrays, the initializer list sizes must exactly match the array sizes, and implicit transposition is allowed for compile-time 1D arrays only.

See also

Array(const Scalar& a0, const Scalar& a1, const Scalar& a2, const Scalar& a3, const ArgTypes&... args)

Constructs a vector or row-vector with given dimension. This is only for vectors (either row-vectors or column-vectors), i.e. matrices which are known at compile-time to have either one row or one column.

Note that this is only useful for dynamic-size vectors. For fixed-size vectors, it is redundant to pass the dimension here, so it makes more sense to use the default constructor Array() instead.

constructs an initialized 1x1 Array with the given coefficient

See also

const Scalar& a0, const Scalar& a1, const Scalar& a2, const Scalar& a3, const ArgTypes&... args

constructs an uninitialized array with rows rows and cols columns.

This is useful for dynamic-size arrays. For fixed-size arrays, it is redundant to pass these parameters, so one should use the default constructor Array() instead.

constructs an initialized 2D vector with given coefficients

See also

Array(const Scalar& a0, const Scalar& a1, const Scalar& a2, const Scalar& a3, const ArgTypes&... args)

constructs an initialized 3D vector with given coefficients

See also

Array(const Scalar& a0, const Scalar& a1, const Scalar& a2, const Scalar& a3, const ArgTypes&... args)

constructs an initialized 4D vector with given coefficients

See also

Array(const Scalar& a0, const Scalar& a1, const Scalar& a2, const Scalar& a3, const ArgTypes&... args)

Copy constructor

See also

MatrixBase::operator=(const EigenBase<OtherDerived>&)

This is an overloaded version of DenseCoeffsBase<Derived,ReadOnlyAccessors>::coeff(Index) const provided to by-pass the creation of an evaluator of the expression, thus saving compilation efforts.

See DenseCoeffsBase<Derived,ReadOnlyAccessors>::coeff(Index) const for details.

This is an overloaded version of DenseCoeffsBase<Derived,ReadOnlyAccessors>::coeff(Index,Index) const provided to by-pass the creation of an evaluator of the expression, thus saving compilation efforts.

See DenseCoeffsBase<Derived,ReadOnlyAccessors>::coeff(Index) const for details.

This is an overloaded version of DenseCoeffsBase<Derived,WriteAccessors>::coeffRef(Index) const provided to by-pass the creation of an evaluator of the expression, thus saving compilation efforts.

See DenseCoeffsBase<Derived,WriteAccessors>::coeffRef(Index) const for details.

This is the const version of coeffRef(Index) which is thus synonym of coeff(Index). It is provided for convenience.

This is an overloaded version of DenseCoeffsBase<Derived,WriteAccessors>::coeffRef(Index,Index) const provided to by-pass the creation of an evaluator of the expression, thus saving compilation efforts.

See DenseCoeffsBase<Derived,WriteAccessors>::coeffRef(Index,Index) const for details.

This is the const version of coeffRef(Index,Index) which is thus synonym of coeff(Index,Index). It is provided for convenience.

This is a special case of the templated operator=. Its purpose is to prevent a default operator= from hiding the templated operator=.

Copies the value of the expression other into *this with automatic resizing.

*this might be resized to match the dimensions of other. If *this was a null matrix (not already initialized), it will be initialized.

Note that copying a row-vector into a vector (and conversely) is allowed. The resizing, if any, is then done in the appropriate way so that row-vectors remain row-vectors and vectors remain vectors.

The usage of using Base::operator=; fails on MSVC. Since the code below is working with GCC and MSVC, we skipped the usage of 'using'. This should be done only for operator=.

Set all the entries to value.

See also

DenseBase::setConstant(), DenseBase::fill()